Robotic systems having tools for removing material from workpieces are well known. One such system is a machining system having one or more cutting tools for forming a workpiece into a desired shape by cutting material from the workpiece. In many cases, the workpiece is generally homogeneous and has a consistent density throughout. Owing to the homogeneous nature of the workpiece, a constant feed rate (e.g., velocity), a uniform tool path, and a constant rotational speed of the cutting tool are often employed and provide efficient, accurate cutting of the material from the workpiece. The feed rate, tool path, and rotational speed employed in these types of systems may be based on characteristics of the material being cut. For example, the feed rate of the cutting tool may be set relatively slower for workpieces formed of denser material. Workpieces formed of denser materials often require slower feed rates in order to maintain consistent cutting accuracy. Otherwise, if the feed rate is set too high for these workpieces, errors may occur as a result of unexpected deflections of the tool, which yields inaccurate cuts. Conversely, for materials having lower densities, relatively faster feed rates may be appropriate, resulting in quicker operating times, while maintaining desired cutting accuracy. Similarly, the tool path of the cutting tool may be set relatively shallower for workpieces formed of denser material in order to reduce heat generation at a tool/workpiece interface. Otherwise, the workpiece may reach temperatures that degrade or damage the workpiece. Likewise, rotational speeds of the cutting tool may be adjusted for different materials to reduce the generation of heat and improve cutting efficiency.
Workpieces such as bone, however, are often non-homogenous and have varying density distributions throughout their volume. As a result, applying a constant feed rate, a uniform tool path, and a constant rotational speed may not be efficient for all portions of the workpiece. Accordingly, there is a need in the art for systems and methods to assist in controlling tools for such non-homogeneous workpieces.